Unpacking the Complexities of the Glen Sannox Ferry Construction

The Glen Sannox, a vessel central to Scotland’s ferry controversy, has now been delivered. This ship, the second largest and most intricate ever constructed for Caledonian MacBrayne, faced significant delays of six years and cost overruns of four times its initial budget, leading to widespread contention. This raises questions about the project’s development and the challenges encountered during its construction. From its inception, the Glen Sannox and its companion vessel, Glen Rosa, were conceived as exceptional CalMac ferries. The specifications issued to prospective builders in 2014 called for a 25% greater carrying capacity compared to existing ships, while maintaining similar dimensions. Furthermore, the vessels needed to be exceptionally manoeuvrable and able to navigate some of Scotland’s most shallow ports. The design mandated identical ships that could operate efficiently at two distinct service speeds. A “key requirement” was also placed on fuel efficiency and lower emissions. To meet this, the ships were designed to be dual-fuel, utilizing both conventional marine gas oil and cleaner liquefied natural gas (LNG). While each of these demands was individually attainable, their combination presented a significant design challenge. Although LNG technology was mature, particularly for larger vessels, only one bidding company possessed experience in constructing such ships, and it represented an unfamiliar area for UK regulatory bodies. Information disclosed to the BBC two years prior indicated frequent disagreements between ferry operator CalMac and CMAL, the government-owned entity